Secretary of State Hillary Rodham Clinton – on her first trip abroad as President Obama’s top diplomat – warned North Korea that it needs to live up to its commitments and dismantle its nuclear programs.

“The North Koreans have already agreed to dismantling,” she said today during a visit in Japan. “We expect them to fulfill the obligations that they entered into.”

While Clinton denounced the North Koreans, the official Korean Central News Agency accused the US of trying to block the country’s “peaceful scientific research” by linking it to a long-range missile test.

During her plane ride to Tokyo, Clinton also blasted the Bush administration for abandoning the 1994 Agreed Framework with North Korea – a deal reached during President Bill Clinton’s first term – that called for the North to give up its plutonium-based weapons program.

The framework collapsed when President George W. Bush accused Pyongyang of maintaining a separate highly enriched uranium program.

As a result, Clinton said, the North had accelerated its plutonium program – allowing it to build a nuclear device that it had detonated in 2006.

Clinton said one goal of her trip was to demonstrate a new US commitment to work with Asian leaders on “problems that no one nation, including ours, can deal with alone.”

North Korea has been advancing preparations ahead of an expected test launch of its most advanced Taepodong-2 missile.

The North has also been stoking tension with its southern neighbor amid relations that have sharply deteriorated since the two countries held a summit meeting in 2007.